Manufacturing Quality Control

The foundation of Hoosier's success as a supplier of ferrite power is our commitment to controlling our manufacturing process. The powder production is monitored and tightly controlled throughout the entire manufacturing process. We use real time statistical tracking software to ensure up to the minute reporting.

Rigorous quality control standards are maintained from mixing our raw materials to producing finished ferrite powder. Production and maintenance personnel, quality technicians, clerical staff, and plant management personnel are dedicated problem solvers and are well trained in understanding the manufacturing process and the expectations of our customers.

Ceramic Quality Check Procedure

Each lot of ceramic powder is quality checked using the following procedure:

Milling

1.3 L steel jar mill
3.0 KG of 0.317 diameter steel balls
200 grams of ceramic ferrite powder
Wet mill additives
325 ml of water
90 RPM mill speed

Allow mill to run for 10 hours to achieve a particle size of 0.7 micron (+/- 0.05 micron) as measured using a Fisher Sub-Sieve Sizer, using a 5.15 gram sample.

Pressing
Concentrate slurry to 70(+5) weight percent solids.

Orienting field----------------------9000 Oersted
Final Pressing Tonnage--------986 KPa
Wet Green Density----------------3.20-3.25g/cm³

Sintering
Sinter to obtain a fired density of 4.95 (+0.05) g/cm³. Typical cycle of approximately ten hours with a peak temperature of 1240° C (+5° C) as determined by Reidhammer rings.

LOI 15-16%

LEEP Quality Check Procedure

Each lot of LEEP powder is quality checked using the following procedure:

Preparation of Binder (Composition B):

Weight in Grams	Material	Manufacturer	Grade
680	Chlorosufonated Polyethylene	Dupont	Hypalon 45
320	Polyisobutylene	EXXON	Vistanex 140
54	Pentaerythritol Ester of Resin	Hercules	Pentalyn G
22	Lubricant	Acme Hardesty	Stearic Acid 60R

Specific Gravity = 1.02

Compounding of the LEEP Ferrite – Binder Mix:
Our mixing equipment consists if a 6 X 12 inch two-roll rubber mill operating at 25 RPM with a friction ratio of 1:1:1. The rolls are heated to a temperature of 99° C and the gap between the roll is adjusted to 0.20 mm. 100 grams of binder is added to the mill first, then 900 grams of ferrite powder is introduced to the mill and mixed by standard techniques. The flexible sheet is finally brought to a thickness of 4.0 mm for magnetic testing by opening the rolls, laminating, and calendaring.

Contact our specialists for powder recommendations or to request a material sample.